In general, there is the one described in Japanese Patent Application Laid-Open No. 2002-51135 as a portable telephone provided with a display device posting incoming call information. This portable telephone is a folio-type portable telephone, which is provided with a character display part on the back surface of a display-side casing provided with a main display part as an incoming call information display part. When there is an incoming telephone call, an LED (light-emitting diode) provided therein as a provided backlight emits light to highlight a character of a telephone pattern to post the incoming call.
While this prior art uses light emission of the light-emitting diode as the backlight and it is necessary to highlight the character display part in high luminance so that the user confirms the incoming telephone call on a separate position, it has been necessary to feed a high current to the light-emitting diode therefor. In other words, this prior art has such a problem that the same cannot light the character display part in high luminance or requires large power consumption even if the former can light the latter in high luminance.
As another prior art, there is the one described in Japanese Patent Application Laid-Open No. 2001-136247. This prior art is a folio-type portable telephone, which is provided with display means consisting of a liquid crystal display device or the like as an auxiliary display part on the back surface of a display-side casing provided with a main display part. The display means digitally displays a numerical value as to the length of a call, while analogly displaying an hourglass.
However, since this conventional apparatus also uses a light-emitting diode as a backlight and the transmittance of the liquid crystal display device is as low as not more than 10%, there is such a problem that the same cannot make display in high luminance or requires large power consumption even if the same can make display in high luminance, similarly to the aforementioned prior art.
An object of the present invention is to obtain a portable apparatus having a display device capable of display of high luminance with low power consumption.
The display device of the portable apparatus according to the present invention can display various indications such as letters and images in high luminance.